JPH01258524A - Routing control system - Google Patents

Abstract

PURPOSE:To reduce the overhead of respective bridges by providing a means to convert a transmission frame from a first LAN of a source routing system to a format inherent to a second LAN except the above-mentioned system. CONSTITUTION:In a network system in which a first LAN21-1 and a second LAN21-2 are connected through a bridge, when a channel from a terminal 22-1 to a terminal 22-2 is set as shown by a heavy line 26, a transmission frame (Fm) 15 becomes like a figure. A bridge (Bg)23-1 knows that itself is a Bg to repeat the Fm from channel information in the Fm15 and fetches the Fm15. The Bg23-1 reads a bridge number '2' of a Bg23-3 and a ring number '2' of a ring 21-2 from the channel information in the Fm15 and makes this into a destination bridge address (DA1)2' of an Fm5'. As a transmitting source bridge address (SA1)3', a bridge number '1' of the Bg23-1 and a ring number '1' of a ring 21 are used, an Fm5 is constituted and this is transmitted onto a ring 20.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a technology for connecting multiple LANs, and particularly to a routing control system using transmission frames.

[Conventional technology]

Conventionally, regarding LAN interconnection using source routing, IE.

802.5. Day-/Day-4, March 10゜1987
, pages 2 to 12 (IEEH802,5D/D
4.

March 10, 1987 p. 2-12).

According to the above conventional technology, IRE! E802LAN and IE
When exchanging information between LANs when connecting LANs other than EE802LAN 1 For example, if the main ring (IEE
In a communication system consisting of multiple sub-rings (IEEE802 LAN) connected to a LAN other than E802 LAN, when one terminal in the sub-ring transmits a transmission frame addressed to a terminal in another sub-ring via the main ring, Each time a bridge located at the connection between the main ring and the secondary ring receives a transmission frame, it searches for the route information contained in the route information field in the transmission frame, and searches the The document discloses a method of determining whether the frame is addressed to a terminal, or converting the format of the transmitted frame as it is at each bridge, and then circulating the frame around the sub-ring.

However, control data such as the destination address sent from the terminal in the transmission format in the sub-ring is not unique in the main ring in most cases, so control is complicated by providing a field for routing control, etc. This resulted in a decrease in throughput as a whole.

An object of the present invention is to provide a routing control method that prevents the above-mentioned reduction in throughput and makes use of the characteristics of each LAN in the above-mentioned system.

[Means to solve the problem]

In order to solve the above object, one aspect of the present invention is to connect a plurality of first LANs according to the source routing method to a second LAN other than the source routing method via a bridge, respectively.
In the network system connected to N, each bridge determines whether a transmission frame received from the first LAN should be relayed by the bridge to the second LAN.

If the received frame is to be relayed, the received frame is converted into a transmission frame having a predetermined format of the second LAN based on the route information contained in the received frame, and this is transmitted to the second LAN. It is characterized in that it is configured to transmit. The conversion of the above frame format is performed, for example, by setting the address of the next bridge included in the route information as the destination address part, the address of the own bridge as the source address part, and adding the main part of the received frame including the above route information part to the information part. The transmission frame for the second LAN is reconfigured in a format having the following format.

[Effect]

According to the present invention, each bridge simply copies the necessary part of the route information in the received frame received from the first LAN using the source routing method, and then transfers the route information to the second LAN.
You can create a frame format that can be sent directly to a destination bridge within the network.

〔Example〕

Hereinafter, nine embodiments of the present invention will be described. FIG. 2 is an overall system configuration diagram of an embodiment of the present invention, showing an IEEE802 LAN (hereinafter referred to as the first LAN) 21-1.21-2 based on the source routing method and a general system not based on the source routing method. LAN (hereinafter referred to as the second LAN)
) 20 are interconnected via bridges 23-1 to 23-3. Each LAN is given a unique ring number 24 within the overall system as shown. Additionally, each of the six bridges is given a unique bridge number 25 within a ring pair. The rules for assigning ring numbers and bridge numbers are in accordance with document IEEE 802.5.

A configuration diagram of the first transmission frame 15 sent out on the first LAN 21-1.21-2 is shown in FIG. 3(A),
The transmission frame 15 is sent to the control unit 10° and the destination address 11.
Source address 12. Route information 13. It consists of an information section 14. Further, the route information 13 includes a route information control unit 16, a ring number 17, and a bridge number 18, which are specific routes.

The last bridge number 19 has no meaning, so it is an arbitrary pattern.

FIG. 3(B) shows the standard format of the transmission frame 5' sent out on the second LAN, in which the control unit 1.
Destination bridge address 2', source bridge address 3
', an information section 4'.

FIG. 1 shows a configuration diagram of a frame 5 circulating on the second LAN 20 in the present invention. This transmission frame is transmitted to the control unit 1. Destination bridge address 2, source bridge address 3. Consists of information part 4, destination bridge address 2
In addition, the ring number 6 of the destination LAN and the destination bridge number 7 are different.

The source bridge address 3 further includes a ring number 8 of the source LAN and a source bridge number 9. The information section 4 includes a frame 15 circulating on the first LAN.
The contents of will be inserted as is.

By using such an address system, the bridge address becomes unique within the second LAN 20.

The information transmission operation according to the present invention will be explained using FIG. Terminal 22- connected to the first LAN 21-1
1 to the terminal 22-2 connected to another first LAN 21-2 is set as shown by the thick line 26. - A transmission frame addressed to the terminal 22-2 sent by the terminal 22-1. 15 becomes as shown in FIG. Bridge 23-
Bridge 23-1 learns from the route information in the received transmission frame 15 that it is the bridge that should relay this frame and takes in the transmission frame 15. Bridge 23-1 knows from the route information in the received transmission frame that it is the bridge that should relay this frame. , read the bridge number "2" and the ring number "2" of the connection bridge 23-3 between the ring 21-2 to which the destination terminal 22-2 belongs and the second LAN, and use these as the destination bridge address of the transmission frame 5. (DA-1) Set it to 2. Also, as the source bridge address (SAI) 3, the bridge number "1" of the own bridge 23-1 and the ring 21 to which the terminal 22-1 belongs
-1, the ring number "1" is used to construct frame 5 in FIG. 5, which is transmitted on ring 20.

By providing the addresses DAI and SAI as described above, each bridge on the ring 20 simply reads the destination bridge address 2 on the transmission frame 5 and compares it with its own bridge, without examining the contents of the information field.
You can instantly determine whether or not the frame is one you should capture.

FIG. 6 shows the basic configuration of the bridge 23 (23-1 to 23-3). The transmission frame 15 circulating on the transmission line 21 is stored in the memory 29 via the LAN adapter 28B, and when it is determined that it should be relayed to the other LAN, it is converted into the frame format on the transmission line 2o, It is sent onto the transmission path 20 via the LAN adapter 28A. 30 is a CPU that performs the above-described judgment operation.

C. Effects of the Invention] According to the present invention, the second LAN that does not use the source routing method is used as the main ring, and a plurality of IEEE802 LANs (the first LAN
) is connected to the 1st L.
The transmission frame relayed from the AN onto the main ring is transmitted to the second L
By converting to a format specific to AN, the second
This reduces the overhead of each bridge connected to the LAN and improves throughput.

[Brief explanation of the drawings] Figure 1 is a diagram showing the configuration of a transmission frame circulating on the main ring without using the source routing method, Figure 2 is a diagram of the overall system configuration, and Figures 3 (A) and (B) are IEEE
L without using 802 LAN and source routing method
The configuration diagrams of transmission frames circulating on the AN, FIGS. 4 and 5, are respectively shown in FIG. 3(A). Figure 6 showing a specific example of a transmission frame corresponding to (B).
The figure shows the basic configuration of the bridge. 1...Control unit, 2...Destination bridge address, 3.
... Source bridge address, 4... Information department, 5...
・Transmission frame in LAN other than IEEE802 of the present invention, 5'... IF, transmission frame when LAN other than EE802 is used alone, 6... Ring number of destination LAN, 7... Destination bridge number , 8... Sender L
AN's ring number 1st rfl 2nd country 3rd mouth (Aan (B) 4th country

Claims (1)

[Claims] 1. In a network system in which a plurality of first LANs that follow the source routing method are each connected to a second LAN that does not use the source routing method via a bridge, each of the bridges receives data from the first LAN. The own bridge determines whether the transmitted frame should be relayed to the second LAN, and if it is, the received frame is forwarded to the second LAN based on the route information contained in the received frame. The transmission frame is converted into a transmission frame having a predetermined format of the second LAN, and is sent to the second LAN.
A routing control method characterized in that a signal is sent to N.